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Kuiper Object Discoveries Formally Announced
ewhac writes "The San Francisco Chronicle is reporting that the new Trans-Neptunian objects mentioned in the press earlier this year are being formally announced this week at a planetary conference in Cambridge, England. Bearing the extremely temporary names 'Xena,' 'Santa,' and 'Easterbunny,' the new objects are quite interesting in their own right (Santa is cigar-shaped, rotates end-over-end every four hours, and has a 60-mile-diameter moon). However, even more interesting is the intrigue behind the press conferences revealing Xena earlier this year. It seems that, using the astronomers' own observation logs (publicly available over the Web) and some key details inadvertently revealed in earlier announcements, someone was planning on 'discovering' the objects first and claiming credit. This was why the scientists 'pre-announced' the existence of Xena back in July, to establish priority. The conference in Cambridge represents the first formal, scientific disclosure of the objects."
How, exactly, would an object that's larger than Pluto, form in the shape of a cigar? It doesn't even make sense...
Real_men_don't_need_spacebars.
As the article points out, this brings the question Pluto's "planet" status to the fore. It never really fit in with the other 8 planets to begin with (compostion, relation to the ecliptic, etc.), but now that both a larger Kuiper Belt Obeject and one with a moon have been discovered, the pure scientist in me hopes that it would be possible to push everyone back towards the idea that there are only 8 planets in our solar system. Read the article. It's worth it just to see the term "plutinos" suggested as a common name for KBOs.
One thing you can say for sure now about Xena, Santa, and the Easterbunny is:
:)
they definitely exist.
std::disclaimer<std::legalese> sig=new std::disclaimer; sig->dump(); delete sig;
"I thought Xena couldn't fly"
"I told you, I'm not Xena. I'm Lucy Lawless."
"I would say that 99 per cent of what my father has written about his own life is false." - L. Ron Hubbard Jr.
Given:
From this we can calculate the brightness of a perfect mirror the size of Pluto if it were in the new object's orbit.
From observations we know that the object is almost as bright as a Pluto-sized mirror would be at this distance.
Thus, the smallest the object can be is 97% the size of Pluto. Since the object cannot be a perfect mirror, it is bigger than Pluto.
Likewise, the reflectivity of other substances can be tried. If the object is made of snow (90% reflectivity) it will be 2% larger Pluto, and if the object has the same composition as Pluto it will be 25% larger than Pluto.
Show me on the doll where his noodly appendage touched you.
Dont be dense.
This planet is billions of km away, and only a few 1000km in diameter.
Its size when viewed from the earth is MUCH lower than the seeing from the athmosphere. In fact its so small that even the spitzer space telescope couldnt resolve it as anything more than a point.
So you have a pointsource.
brightness of the point= (light from planet)/(distance from earth)^2
light from planet=light recieved from sun*albedo
light recieved from sun= constant*(area of planet disc)/(distance from sun)^2
-> brightness oft the point= albedo*solar constant*(radius of planet)^2*pi/(distance from sun*distance from earth)^2
You know the solar constant, you know the distances, and you know that the albedo cannot bigger than 1 (perfect lambertian reflection).
If you just meassure the light recieved from the point, you have only albedo and radius left, which allows a minimum size estimate)
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?